Echo using CM 3.0(11) and 7940/60

[jan.palmann]

Running CallManager 3.0(11) and using Cisco phone 7940 & 7960, our customer suffers echo problems. What load would provide the least echo these days :v) Is there a place to search for this, or is it answered via TAC in every case ?

Regards Jan

[duc-vu]

Jan,

Do you have echo problem between IP phones or IP phones and PSTN ?

Duc

[jan.palmann]

Hi Duc,

Sorry about the delayed answer, here it is. Our customer has echo between IP phones and the PSTN. It vary'es from time to time, and effects about 50% of the calls in and out of the house

Jan

[ptalbot]

What gateway and protocol is in use? You can increase the delay window on the echo canceller and eliminate the echo in most cases.

Pat

[jan.palmann]

The gateway is 3600 running IOS (tm) 3600 Software (C3640-IS-M), Version 12.2(5.4), connected via a ISDN PRI.

The protocol is G.711

I tryed ajusting the echo delay, as well as the signal levels, as recommended in this forum, but it's not to the customers liking.

Jan